Switchable polarity materials (SPMs) exhibit characteristics useful in a wide range of applications. As used herein, the term “switchable polarity material” means and includes a material that is configured to undergo a polarity shift when subjected to a change in reaction conditions (e.g., the addition or removal of a gas). For example, an SPM may switch (e.g., convert) from a non-polar form (e.g., a hydrophobic from) to a polar form (e.g., a hydrophilic form) when subjected to the change in process conditions, or may switch from a polar form to a non-polar form when subjected to the change in process conditions. The non-polar form and polar form of the SPM may each have a different solubility in a solvent, such as water and/or an alcohol. U.S. patent application Ser. No. 13/480,053, filed May 24, 2012, the disclosure of which is hereby incorporated herein in its entirety by this reference, describes methods and systems for liquid treatment utilizing various switchable polarity materials.
Unfortunately, conventional methods and systems for producing a polar form of various SPMs can be excessively time consuming, inefficient, and/or complicated. For example, conventional methods and systems for producing the polar form of various SPMs typically employ batch processes wherein gaseous carbon dioxide (CO2) is bubbled through a stirred heterogeneous mixture of water and the non-polar form of the SPM. Such processes rely on relatively inefficient mass transfer between the gaseous CO2 bubbles and the heterogeneous mixture of water and the non-polar form of the SPM, and can take relatively long periods of time (e.g., weeks) to form relatively small batches (e.g., 0.5 liter batches) of product exhibiting desirable concentrations of the polar form of the SPM. Accordingly, such processes and systems can be insufficient for the needs of many industrial applications.
It would be desirable to have new methods and systems for producing polar forms of SPMs. It would further be desirable if the new methods and systems facilitated increased conversion efficiency, and were relatively inexpensive and simple in operation.